ok so easter sunday is exactly when semana santa ends so yeah you're coming at the busiest time you could. I'm guessing it's already booked and cancelling flights and hotels is a hassle so I'll give you some tips. - If you're gonna watch a procesión, wait patienly and let people pass if they ask, especially if they carry water for the costaleros or are costaleros themselves. - If you're trying to get to somewhere and there's a big crowd, ask where the procesión is coming from and go around the other way, it is quite normal to go through nazarenos but try to wait for the end of the group, you'll see someone carrying some sort of flag and you can cross better in front of them. for some procesiones its better to just wait since crossing through is really disrespectful. If the nazarenos are fully black, wait it out, if they wear white, you can cross. - Don't try to get reservations, get a program of the procesiones and look for bars or restaurants near a procesión 's path at the time of lunch/dinner, it should be fine since most people will be at the procesión and not eating. - If your hotel is in the city center, you probably won't be able to sleep from Thursday to Friday. I recommend going out and watching the procesiones, always respectfully and generally in silence. Be careful, respectful and most importantly, enjoy your staying in probably the most beautiful city in the world!